The great order of Ungulata is represented by various forms of sheep, as many as ten or twelve wild species of Ovis being met with in the mountain chains of Asia; and more sparingly by several peculiar forms of antelope, such as the saiga (Saiga tatarica), and the Gazella gutturosa, or yellow sheep. Coming to the deer, we also meet with characteristic forms in northern Asia, especially those belonging to the typical genus Cervus.
As ancestors of the Artiodactyle section of the Ungulata, we may look to forms more or less closely related to the North American Lower Eocene genera Mioclaenus and Pantolestes, respectively typifying the families Mioclaenidae and Pantolestidae.
All Ungulata probably originated from Condylarthra.
The Perissodactyla have been brigaded with the Artiodactyla to form the typical group of the ungulates, under the name of Diplarthra, or Ungulata Vera, and the features distinguishing the combined group from the less specialized members of the order Ungulata will be found under the heading of that order.